The US Secretary of State John Kerry has arrived in Geneva, to try and secure a landmark deal with Iran on its nuclear programme.

He's joining foreign ministers from Britain, Russia, China, France and Germany for the talks.

It's after negotiations earlier this month failed to reach agreement.

Negotiators have been trying to persuade Tehran to curb its nuclear activities in exchange for the lifting of international sanctions.

This third meeting since the Iranian President Hassan Rouhani's election in June. It is seen as the biggest hope in years to resolve the decade-old standoff over Iran's nuclear programme.

Failure might mean Iran resuming the expansion of its atomic activities, while Washington and others could toughen already painful sanctions and the possibility of Israeli military action would draw nearer.

According to a draft proposal hammered out on November 9, the US, Britain, China, France, Russia, and Germany - the so-called P5+1 nations - want Iran to freeze key parts of its nuclear programme for six months.

In return Iran would get minor and, Western officials insist, "reversible" sanctions relief, including unlocking several billion dollars in oil revenues and easing trade restrictions on precious metals and aircraft parts.